Such locks are used for selectively locking an unlocking various different types of products that have a first part, which is movable in relation to a second part. Examples of such products are buildings, lockers, furniture, boxes, cases and suitcases. Another example is containers such as dispensers for consumable materials in kitchens, toilets or similar. Such containers are often required to be locked, in particular when located in more public places. It has become necessary to be able to lock the container to prevent the entire contents of the container from being removed by unauthorized an person, while at the same time allowing successive feeding out of for example contained paper, washing substances or the like. Re-filling of the container is then carried out by authorized persons having access to a key for unlocking the container or dispenser. However, for containers intended for smaller workplaces, for private use or similar it may be an inconvenience to keep track of the respective key and to unlock the container for refilling of the consumable material. As the task of refilling may be carried out by more than one person it is often not desirable to lock the container.
A natural placement of the key is inside the container, but placing the key somewhere in the container without a suitable release means would mean that the key becomes locked inside, in the case that the lock is of the self-locking type with spring-return to the locking position upon closing of the container, which in turn would lead to obvious difficulties.
WO 92/018733 describes one lock arrangement that addresses this problem. The locking ability is achieved by means of a lock, the main part of which is arranged in the cover and presents a locking cylinder with a slot, in which is arranged a key for locking and unlocking. The lock has a lock catch rotatable by means of the key, said lock catch being adjustable between a locking position and a free position. As part of the lock there is arranged a locking edge in the console which, in the shown example, is formed by an opening edge portion of an opening arranged in the console. According to this document, the container presents a holder for the key arranged internally, which holder is positioned so that, with the key placed in the holder, the lock is prevented from assuming the locking position. In this free position, the container is maintained closed by a snap-lock that may be opened by hand.
A problem with this solution is that the container is not properly locked when it is desired to allow the container to be opened by hand, without using a key. A further problem is that the above solution requires a separate snap-lock to be provided in order to maintain the container closed when the key is not used, adding to the complexity of the container as well as the cost for materials and assembly.
U.S. Pat. No. 3,500,667 discloses a combination locking and latching device which functions either as a key-operated lock or as a push button operated latch. The device comprises a housing plate and a spring which together define a housing which accommodates a barrel and a rotatable hammer with a hook. The spring is at one end attached to the inside of a first portion of a cabinet. The hook may engage a flange which is arranged at a second portion of the cabinet, which second portion is separable from the first portion. When the device is operated as a push button latch, the housing together with the barrel and the hook are pushed inwardly away from the inside of the enclosure, whereby the hook is disengaged from the flange. In order to prevent the device from being operated as push button operated latch, the device further comprises a bar which is slidably mounted to the second portion of the cabinet. By securing the bar in a first position the hook is prevented from being disengaged from the flange by pushing the housing together with the barrel and hammer. The hook may then only be disengaged from the flange by rotating the barrel and the hammer. By securing the bar in a second position the hook is allowed to be disengaged from the flange by pushing the housing together with the barrel and hammer. The hook may then be disengaged from the flange either by pushing the housing or by rotating the barrel and hammer.
During push button operation, the barrel is moved out of engagement from an opening which is arranged in the first portion of the cabinet for giving access to the device from the outside of the cabinet. Due to the construction of the device including the spring, the housing which accommodates the barrel and the hammer will be displaced along a curved line during push button operation. Such an arrangement causes problems in regard of the overall tightness of the cabinet. Additionally, at the device according U.S. Pat. No. 3,500,667 a special tool is required for securing the slidable bar in either of the first and second positions to thereby set the device in either of the operational modes. Such setting of operational mode may further be carried out only from the inside of the cabinet.
Also at other products or items provided with a lock, it may in some instances be desirable to prevent unauthorized access by requiring a key, whereas in other instances it is desirable to allow free access for anyone.
The invention aims to provide an improved lock to solve the above problems and to facilitate handling of the product or item provided with the lock.